ENTOMOLOGY 156 BIOLOGY OF PARASITISM

LABORATORY 1: PLANT PARASITIC NEMATODES

EXPLANATION OF DEMONSTRATIONS

For nematode specimens under dissecting microscopes, observe general size and shape and presence of stylet. For nematodes on slides under compound microscopes, observe markings on cuticle (if any), stylet in more detail, and shape of esophagus. Refer to handout for pictures and descriptions of distinctive characteristics of each genus. For plant specimens under dissecting microscopes and preserved specimens in bottles observe symptoms (refer to handout for description and to color photos with demonstration). Plant parasitic nematodes are found in each of the two major classes of the Phylum Nemata (or Nematoda) the Adenophorea and the Secernentea. Your should be able to observe distinctive differences in the esophagi and stylets of each class. A simplified classification of the phylum emphasizing groups containing parasites is included with this handout. Families for which we have examples are marked. Demonstrations are set up in the order they are listed on the classification chart. The chart also indicates the relative evolutionary position of the various taxa (least derived at the top, most derived at the bottom). In the next laboratory we will look at parasites of many of the invertebrates and vertebrates on the chart. On the lab practical you will not be asked to specifically identify a nematode to genus but should be able to recognize that the specimen is a nematode, the morphological characteristics used in classifying nematodes (e.g. type of feeding apparatus, type of esophagus, whether the nematode is a male or a female, and the presence or absence of a bursa or spicule), and the Order to which the nematode belongs.

CLASS ADENOPHOREA

ORDER DORYLAIMIDA

Longidorus africanus (needle nematode) (1) live under a dissecting microscope, (2) at higher power under a compound microscope.

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